After age 30, we lose 18 million brain cells per year. However, we also grow billions of new dendrite connections as we age. Scientists recently busted the age-old belief that as we grow older, we naturally start losing intelligence and memory. In tests matching healthy 70-year-olds and 20-year-olds, the old folks outperformed the youngsters in long-term memory tests, and fell slightly behind in short-term memory. However, with practice, they could learn to hold their own in short-term memory tests too.